Effect of milling time and investigation of thermodynamic analysis on amorphous phase formation in Fe-C-Ta alloy prepared by mechanical alloying

نویسندگان [English]

E Bahadori yekta1؛ A.H Taghvaei2؛ Sshahriyar Sharafi3

1Department of Materials Science and Engineering, shahid bahonar University of kerman, kerman, Iran

2Department of Materials Science and Engineering, Shiraz University of Technology, Shiraz, Iran

3Department of Materials Science and Engineering, shahid bahonar University of kerman, kerman, Iran

چکیده [English]

Nowadays, soft magnetic materials such as nanocrystalline and amorphous alloys with unique physical, mechanical and magnetic properties have attracted much attention. Recently, Fe-based amorphous alloys have been greatly developed due to their excellent magnetic properties and relatively low cost. In this study, effect of milling time on microstructure of Fe-C-Ta alloy prepared by mechanical alloying was studied. Besides, the possibility of glass formation was investigated according to thermodynamic calculations, performed based on advanced Miedema model. The X-ray diffraction (XRD) results proposed that the fraction of amorphous phase enhances by increasing milling time up to 70 h, and then it becomes unchanged up to 90 h milling. Moreover, the differential scanning calorimetry (DSC) results confirmed the formation of amorphous phase with a crystallization temperature of 678 K, after 70 h of milling. The thermodynamic calculations with respect to the advanced Miedema model revealed that the Gibbs free energy changes for glass formation (-42.35 kJ/mol) are larger than those of solid-solution formation (-28.5 kJ/mol) and consequently, the amorphous phase has a larger tendency to form after milling.